I'm having problems with my mesh causing divergence. I'm trying to replicate the results in this PDF here but the mesh I've created has issues are causing simpleFoam to diverge. For some reason, the solution is only diverging at higher angles of attack.

I've put together a set of pictures showing the problem and my geometry. They are located here. For some reason, all along the join between the four hex blocks, the solution diverges. The most extreme example is the portion pictured in the album.

I'm not sure if the non-ortho faces that checkMesh finds are the source of the problem. There are some right at the wingtip, where the most extreme divergence is, but the divergence continues all the way out, but there are no non-ortho faces that far out.

I'm hoping that one of you can tell me how to fix the problem without having to re-do the whole blockMesh file. Or, if you say that's not possible, to give me recommendations on how to make this geometry without causing bad cells and faces in the mesh. I'd like any suggestions to keep in mind that I will be changing things like airfoils and aspect ratio, so it should be automation friendly.